Could a hybrid system halve coal plant emissions?

Slashing greenhouse gas emissions hasn’t always been an easy task for the coal industry but a new process is believed to potentially change that.

Researchers at the Massachusetts Institute of Technology (MIT) have been working on a plan to find a cleaner way to use coal and reduce emissions.

The method proposed by Professor Ronald Crane and doctoral student Katherine Ong would double the amount of electricity produced for each unit of coal, which means emissions produced per unit of power would be cut in half.

Coal gasification is a way of extracting burnable gaseous fuel rather than burning it. The process is widely used in chemical processing plants as a way of producing hydrogen gas.

Fuel cells produce electricity from a gaseous fuel by passing it through a battery-like system where the fuel reacts electrochemically with oxygen from the air.

An illustration of the combined system proposed by MIT researchers. Image: Jeffrey Hanna/MIT

The researchers believe combining them in a single plant would allow them to exchange heat with minimal energy losses. They add the fuel cell would generate enough heat to sustain the gasification part of the process, eliminating the need for a separate heating system which is usually provided by burning a portion of the coal.

Sine no burning is involved in producing the power, fewer pollutants such as ash and Carbon Dioxide are produced.

Existing plants are said to convert around 30% of the coal burned into energy however the researchers predict the new technique to increase efficiency by 55% to 60%.

Ms Ong said: “If we’re going to cut down on Carbon Dioxide emissions in the near term, the only way to realistically do that is to increase the efficiency of our fossil fuel plants.”